Differential pressure, and temperature control valve system.



J. C. HORNUNG. DIFFERENTIAL, PRESSURE, AND TEMPERATURE CONTROL VALVESYSTEM APPLICATION FILED JULY 27,1912.

2 SHEETS-SHEET 1v Patented June 16, 1914.

J. G. HORNUNG.

DIFFERENTIAL, PRESSURE, AND TEMPERATURE CONTROL VALVE SYSTEM.

APPLICATION FILED JULY 27, 1912.

1,100,077, Patented June 16, 1914.

2 SHEBTSSHBBT Z.

lllllllllllllinlll lflllll'lllllllll I tems, of which the following is aspecifi JOHN C. HORNUNG,.OF CHICAGO, ILLINOIS.

DIFFERENTIAL. PRESSURE, AND -'rEM'1 1tATURE CONTROL VALVE SYSTEM.

To all whom it may concern: 1

Be it known that I, JOHN C. Hormone, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Diiferential,-Pressure,and, Temperature Control Valve Syscation.

My invention relates to central station heating and has particularreference to a system comprising a combination of valves and connectionswhereby to maintain within the house piping a predetermined difler-.

ential head of pressure between the inlet to and the outlet from saidpiping irrespective of fluctuations of pressure in the supply and returnmains, the maintenance of said predetermined differential being in turncontrolled automatically by variations of temperature in the apartmentso that in comparatively warm weather the differential head may bemaintained lower than in extremely cold weather and vice versa, theupper limit of the differential being Hired by the adjustment of thedevice.

In central station heating the pressure Within the mains varies greatlyat the point of leaving the centralstation and the point of returnthereto and consequently'the pressure at an entrance toa house near thecentral station is much higher than at a distance therefrom while thepressure in the return main is much lower in the near house than it isat the more remote one. It may happen, for instance, that the entrancepressure from the supply main at the near house is 60 pounds while thepressure 'at the discharge therefrom to the return main at that pointmay be 10 pounds, adiiference of pounds; and near the end ofThe main thedifference in pressure between the two may not exceed 8 or 4 pounds. I

In order to insure the properfiow of the heating fluid through the housepiping it is necessary that there shall be a difi'erential pressure atthe inlet to and the outlet from the house or head of pressure inthe'house piping which head will depend upon theheight of the building,the length of the'piping and the number of radiators which measure the"friction within said house piping. Under ordinary circumstances a headof pressure within the house or a differential bet-ween the inlet andoutlet of 2 pounds is suflicient and an increase of the head beyond thisSpecification of Letters Patent.

central station that Patented June 16, 1914.

Application filed July 27,- 1912. Serial No. 711,965.

point is waste of the heating power while a decrease below this pointwill insufficiently heat. the house. It is to maintain thisdifl'erential press'ure within the house piping constant under givenweather conditions and unaffected by fluctuations in the supply andreturn mains at whatever distance from the the present invention isdesigned; 1 4 In, the accompanying drawings I have illustrated apreferred embodiment of the invention, from which taken in connectionwith the following detailed description based thereon the invention willbe readily understood.

In these drawings; Figure 1 represents a vertical section through aportion of a house showing in a diagrammatic manner a house systemembracing the invention, and Fig.2 is an enlarged elevation partly insection of the form of differential temperature and pressure controlvalve preferred by me.

In the drawing the reference numeral 11 designates a pipe leading fromthe. supply main, and 12 designates a pipe leading to the house heatingsystem. The heating fluid passing from one of these pipes to the othertraverses the valve casing 13 entering first the valve chamber 14 andthence by way of the twin ports 15 and 16 to the valve chamber 17 whichlatter isin communication 1 through the cylinder 21 into the upper space22 of a diaphragm casing 23 where said stem is attached by means of a-pin24 .to the upper face of a diaphragm 25 whi le the lower face ofsaid diaphragm bears upon a coil spring 26 disposed within the housing27 and adjustable as to tension by means of the screw bolt 28 threadedwithin the lower portion of the housing 27 and capable of adjustmenttherein by means of its angularshank arranged to cooperate with asuitable tool, the screw being covered by a cap 29.

The operation of the pressure control valve thus far described is wellknown. 'The object of this valve is to maintain a constant head ofpressure withinthe valve chamber 17 and the pipe 12, which pressure isless than that within the valve chamber 14 and the pipe 11. By reason ofthe fact that the valve stem is attached to the upper face ofthediaphragm 25 and by reason of the further fact that the upper space22 within the diaphragm casing is in communication by the ports 30, 30and the interior of the cylinder 21 with the valve chamber 17, while thelower face of the diaphragm is acted upon by the adjustable spring 26,the valve is balanced when the pressure within the valve chamber 17 isequal to the tension of the spring 26 and the valve is held closed bythe weight of its parts. If the pressure within the valve chamber 17drops below that for which fluid pressure on the upper side of thediaphragm becomes less than the spring pressure on the lower sidethereof and the preponderance of the spring pressure opens the valvepermitting additional fluid to pass from the valve chamber 14 throughthe ports 15 and 16 to the chamber 17 to restore the normal pressurewithin the house system. If, however, weather conditions are such as torequire a lower head of pressure within the house system to maintain apredetermined temperature; within the apartment, it is desirable thatthe pressure .control valve be automatically influenced so as not to actin the normal manner. Having in view such conditions and with the objectof controlling said valve by the temperature within the house, I providein combination with the pressure control valve as described atemperature control valve acting directly upon and influencing theaction of the pressure control valve, as shown in Fig.2.

The top of the valve casing 13 is tapped at 31 and has threaded thereina bushing 32. Upon this bushing 32 is mounted a. diaphragm chamber 33the diaphragm 34 of which has its upper face exposed to the space 35within said casing while its lower face has attached thereto a plunger36 guided within the yoke 37 and the bushing 32, the lower end of theplunger resting upon the upper face of the valve 18. Springs 38, 38supported by the yoke37 bear upon the lower face of the diaphragm 34while the surface 35 above the diaphragm is in communication by means ofthe pipe 39 with a thermostatic motor valve 40 of any well knownconstruction whereby in the" usual manner a pressurefiuid supplied bythe pipe 41 is admitted to or exhausted from the space 35 according asthe temperature in the apartment rises above and falls below apredetermined degree.

The "action of the temperature control valve upon the pressurecontrolvalve is as follows: If the temperature rises above that forwhich the thermostat is set, pressure fluid will be admitted to thespace 35 forcing the diaphragm 34 and its plunger 36 downward until itslower end bears upon the upper face of the valve 18 whereby the valves18 and 19 will be held more, nearly or quite closed even though thepressure within the spring 26 is adjusted, the

application for turn main and to maintain have devised further constantunder a reduced head of pressure within the house system.

The construction thus far described is the same as that set forth andclaimed in my patent filed concurrently herewith andwill of itselfresult, as previously stated, in maintaining within the valve chamber.17 at the entrance to the house piping a pressure which cut of that inthe valve chamber 14 on the supply side of the valve. In order, however,to render the flow within the house piping independent of fluctuationsin the rewithin the house piping a predetermined head of excess ressureat the inlet over that of the out et I constructional features \VlllCllcombine, with the pressure control and with or without the temperaturecon trol, a difi'erential control whereby the system is rendered -whollyautomatic for the y purpose stated.

he pressure within the, house pipin is, as will be readily understood,unafi'ecte by 42 pressure fluct ations in the supply main by reason ofthe interposed pressure control valve 13. -Variations of pressurehowever in the return main 43 are transmitted to the house piping byreason of the unobstructed communication between said return maln 43 andthe outlet v Under old conditions fluctuations in the return main exertadisturbing effect on the head of pressure in the house piping so thatit has been impossible, to maintain therein a constant differential orhead of pressure. By my invention I provide for the equalizlng of anyincrease or decrease in pressure at the outlet from the house bysimultaneously and to an 'equal extent increasing or decreasing thepressure at the inlet to the house piping through the pressure controlvalve.

By reference to Fig. 1 of the drawing it will be seen thatI provide across connection 45 between the outlet pipe 44 and the space 46 belowthe diaphra 25 of .the pressure control valve, so tha the lower, side ofthe diaphragm in the valvetopening direction is exposed to the pressureof the heating fluid at theroutletfrom the house piping. If, as beforeassumed, the pressure in the valve supply chamber 14 is 60 pounds andthe pressure in the valve chamber 17 at the inlet of the house piping bedesired to? be maintained at say 12 pounds in order to secure a head ofpressure or differentiallof 2 is independpipe 44 from the house.

pressure of 10 pounds in the pipe 45. makes a total pressure of 12pounds on the lower side of the diaphragm, which total pressure isbalanced by the pressure of 12 pounds within the house inlet pipe 12 amlthe valve chamber 17 communicated to the space 22 above the diaphragmthrough the openings 230. In this balanced condition the weight of thevalve and stem will maintain the valve closed. If, however, thedifference bet ween the pressure in the pipes 12 and 45, which measuresthe head of pressure within the house, drops below the desired 2 poundsdifferential by reason of the falling of the pressure in the pipe 12.the 10 pound pressure in the pipe 45 added to the two pounds pressure ofthe sprin 26 will lift the diaphragm and open the valve admittingfurther fluid from the supply side of said valve which is incommunication with the high pressure supply main, and as soon as thepressure in the pipe 12 is restored to 12 pounds the valve will close.

It will be understood that in practice the pressure control valve willremain slightly open so as to supply just enough fluid to the valvechamber 17 to maintain a constant flow through the inlet pipe 12 of thehouse piping the amount of the flow being governed by the differentialbetween the inlet and outlet which is regulated by the tension of thespring 26, whereas if from any cause the differential falls below therequired head the valve will open wider and if it rises above suchpredetermined head the valve will entirely close until the properdifferential is restored. If for instance the pressurein the return main43 at the outlet from the pipe 44 drops to 9 pounds the pressure in thepipe 45 Will likewise drop to 9 pounds, which, added to the 2 poundspressure of the spring 26, makes a total of 11 pounds, a forceinsuflicient to balance the pressure of 12 pounds in the pipe 12 andconsequently the valve will be held tightly closed by the pressure onits upper face until the pressure in the pipe 12 drops to 11 pounds whenthe valve will again be balanced and will maintain this differential of2 pounds between the pressure of 11 pounds at the inlet and 9 pounds atthe outlet. If on the other hand the pressure in the return main 43rises to say 15 pounds, this increase of 5 pounds is instantlytransmit-ted through the pipe 45 to the lower side of the diaphragm 25and being added to the 2 pounds pressure of the spring 26 a totalpressure of 17 pounds is exerted upon the under side of the diaphragmopening the valve against the pressure of 12 pounds on the upper side ofthe diaphragm and the valve is held open until the, pressure upon theupper side of the diaphragm and in the valve chamber 17 and the pipe 12is raised to 17 pounds when the valve will again become balanced andthere will he maintained under such conditions the constant differentialof 2 pounds over the inlet pressure 17 and the outlet pressure of 15. 7

While under ordinary conditions it may be found that a differential of 2pounds is required to maintain a suflicient flow through the system toproperly heat the house a less differential or a lower head of pressuremay be amply sutticient in comparatively warm weather and under suchcircumstances the temperature control valve 33 will operate inopposition to the spring 26 to maintain the pressure control valve lnorenearly or quite in its closed position if the temperature in the room istoo high even though the head of pressure within the house piping mayhave dropped below the pounds for which it was set by the spring 26. Theaction of the pressure control valve will thus be modified or heldinoperative until the temperature within the room lowers to such anextent that the plunger 36 of the temperature control valve 33 iswithdrawn from the upper face of the valve 18 when the pressure controlvalve will resume its normal functions and the head of pressure withinthe house piping will be restored.

It will be understood that the form of valve shown, even if thetemperature control feature is inactive or omitted, will be eflicientfor the purpose of maintaining within the house piping system apredetermined ditferential pressure at the inlet and outlet so that thehead and resultant flow therein will be constant, the upper portion ofsuch valve coming into operation only if the temperature in the buildingrises above that for which the device is set and operating at such timeto maintain the differential head suiiiciently low to accord with thereduced circulation required to maintain such predetermined temperature.

I claim:

1'. A heating system comprising in combination a supply main, a returnmain, house piping connected therewith and including arranged to act onsaid valve to modify the operation thereof, substantially as described.

2. A heating system comprising in combination a supply main, a returnmain, house piping connected therewith and including friction media, adiaphragm operated pressure controlled valve interposed in the systembetween the supply main and the friction media, the diaphragm exposed inthe valve closing direction to the fluid pressure at such point, a crossconnection between the opposite side of the diaphragm and the system ata point between the friction media and the return main whereb to exposesaid diaphragm in a valve opening direction to the fluid pressure in thesystem at such latter point, and means arranged to'vbear upon said valveat a certain predetermined temperature to modify the operation thereof,substantially as described.

3. A heating system comprising in combination a supply main, :1 returnmain, a house piping connected therewith and ineluding friction media, adiaphragm-operated pressure controlled valve interposed in the systembetween the supply main and the friction media, the diaphragm exposed inthe valve closing direction to the fluid pressure in the system at suchpoint, a cross connection between the opposite side of the diaphragm andthe system at a point between the friction media and the return mainwhereby to expose said diaphragm in a valve opening direction to thepressure in the system atsuch latter point, adjustable yielding meansacting on the valve in a valve opening direction, and thermostaticallycontrolled means acting on said valve in opposition to the adjustableyielding means whereby to modify the operation of the valve,substantially as described.

4. A heating system comprising in combination a supply main, a returnmain, house piping connected therewith and including radiators, adiaphragm operated pressure controlled valve interposed in the housepiping between the radiators and the supply main, a diaphragm exposed inthe valve closing direction to the pressure in the house piping attheinlet from the supply ain, a cross connection between the oppos teside of the diaphragm and the house piping be tween the radiators andthe return main whereby to expose the said diaphragm in a JOHN C.HORNUNG.

Witnesses:

W. H. SGHOTII, ARTHUR F. LINDLEY.

